Duplex mailing envelope



y 1964 H. c. FITZGERALD DUPLEX MAILING ENVELOPE 3 Sheets Sheet 1 Filed May 31, 1961 FIG.

INVENTOR.

HENRY C. FITZGERALD BY FIGS fif mee m ATTORNEYS y 4, 1964 H. c. FITZGERALD DUPLEX MAILING ENVELOPE 3 Sheets-Sheet 2 Filed May 31, 1961 V w wwl INVENTOR.

HENRY C. FITZGERALD BY ATIORNEYS y 1964 H. c. FITZGERALD 3,140,817

DUPLEX MAILING ENVELOPE Filed May 31, 1961 3 Sheets-Sheet 3 FIGS INVENTOR. HENRY c. FITZGERALD ATTORNEYS United States Patent 3,140,817 DUPLEX MAILING ENVELOPE Henry Q. Fitzgerald, Belmont, Mass, assignor to Ames Safety Envelope Company, Somerville, Mass, a corporation of Massachusetts Filed May 31, 1961, Ser. No. 113,706 1 Claim. (Cl. 229--72) This invention relates in general to mailing envelopes and more particularly concerns a novel duplex envelope fabricated from one piece of paper blank of unique configuration which folds into a double compartment envelope that is expansible from front to back.

There are commercially available a number of diiferent style envelopes in a wide range of sizes designed to meet various needs. Many of the larger size envelopes, which are intended to accommodate bulky materials, are frequently provided with smaller envelopes for enclosing letters, bills, and the like. These smaller envelopes very often are of the window type wherein the forwarding address is placed on the covering letter, or bill, in such a position that, when the letter is subsequently folded and inserted in the smaller envelope, the address will appear in a rectangular window cut through the front of the smaller envelope.

This smaller envelope is normally pasted on the front panel of the larger envelope, although in some cases it is mounted on the inside of the larger envelope. With this latter arrangement, a second window must be cut through the front panel of the larger envelope in register with the window in the smaller envelope. Particular care must be taken when assembling the smaller envelope within the larger one to insure that the windows of each are precisely aligned with one another.

In any event, double envelopes are relatively difiicult and expensive to manufacture since two separate envelopes must be independently fabricated and subsequently bonded together.

Accordingly, it is an object of the present invention to provide a double compartmented, expansible and windowed envelope of simple design and one that is easy and inexpensive to produce.

Another object of this invention is to provide a double compartment envelope which is formed from a single piece of sheet material.

Yet another object of this invention is to provide a one piece, double compartment envelope that is expansible at least as to one of its compartments.

More particularly, this invention features a double compartment envelope formed from a single blank of sheet material characterized by a rear panel section having a pair of intermediate panel sections hinged by accordion pleat sections to opposite side edges of the rear panel section. A front panel section is hinged to the lower edge of the rear panel section and a gummed flap is hinged to the upper edge of the rear panel section or to the lower edge of the front panel section. When forming the blank into an envelope the two intermediate panel sections are folded back and joined in overlapping relation against the rear panel section to form a first compartment. The front panel section is then folded back against the folded intermediate panel sections to form with them a second compartment. The hinged flap may thereupon be folded down to seal the two compartments.

But these and other features of the invention along with further objects and advantages thereof, will become more readily apparent from the following detailed description taken in connection with the accompanying drawings in which:

FIG. 1 is a plan view of an envelope blank made according to the invention,

3,140,817 Patented July 14, 1964 FIG. 1a is a fragmentary view of FIG. 1 on an enlarged scale showing the various crease and fold lines of the envelope blank,

FIG. 2 is a view similar to FIG. 1 but showing the reverse side of the envelope blank,

FIG. 3 is a plan view showing the envelope in a partly formed condition,

FIG. 4 is a plan view of the envelope with the flap in an open position,

FIG. 5 is a view similar to FIG. 4 but showing the flap in a closed position,

FIG 6 is a plan view of an envelope blank embodying a modification of the invention,

FIG. 7 is a View similar to FIG. 6 but showing the reverse side of the blank,

FIG. 8 is a plan view showing an envelope partly formed from the blank of FIG. 6,

FIG. 9 is a plan view of the modified envelope with the flap in an open position, and

FIG. 10 is a view similar to FIG. 9 but showing the reverse side of the envelope.

Referring now to the drawings, the reference character 10 generally indicates an envelope blank, preferably of heavy manila paper, or the like, from which a onepiece, double compartmented and expansible envelope is formed. The blank 10 shown in FIG. 1 is organized about a rectangular rear panel section 12 having a tongue or flap 14 hinged thereto along a fold line 15 which defines the upper edge of the rear panel section 12. A front panel section 16 is hinged to the rear panel section 12 along a fold line 17 which defines the lower edge of the rear panel section. As illustrated, the front panel section 16 is provided with a generally rectangular window 19 which may be masked by a transparent insert 21, if desired.

Hinged along fold lines 18 and 20, which define the side edges of the rear panel section 12, are a pair of accordion pleats 23 and 25. Extending out from the pleats 23 and 25 and hinged thereto along fold lines 26 and 27 are a pair of intermediate panel sections 22 and 24 of generally rectangular shape although they may taper to some extent along their upper edges if desired.

The pleats 23 and 25 are each formed at their upper portions with slightly rounded shoulders 28 and 29 which have their upper edges even with the fold line 15 and their side edges even with the fold line 26. Center fold lines 30 and 31 extend parallel to the fold lines 18 and 26 to form the accordion pleats. Diagonal portions 32 and 33 extend between the side edges of the front panel section 16 and the lower edges of the pleats 23 and 25 terminating at the fold lines 30 and 31.

In the envelope blank illustrated in FIGS. 1 through 5, pressure sensitive or moisture activated adhesive 34 has been applied to selected marginal areas so that the several panel sections will attach permanently to one another when folded into position.

As shown in FIG. 3 the first step in forming an envelope from the blank 10 is to fold the intermediate panel sections 22 and 24 back in overlapping relation against the rear panel section 12. Simultaneously, the accordion pleats 23, 25 are folded inwardly between the intermediate panel sections and the rear panel sections, with the diagonal portions 32 and 33 being folded against the front panel section 16. As will be readily understood, the intermediate panel sections, together with the rear panel section and the accordion pleats, when folded, form a first compartment that is expansible from front to back.

A second compartment is formed by folding the front panel section 16 back against the folded intermediate panel sections as shown in FIG. 4. The facing marginal portions of the front panel section and the folded intermediate panel sections are provided with an adhesive so that the several sections will bond together when folded into position. The second compartment may accommodate a covering letter or other first class mail as desired. As is customary in duplex envelopes, the forwarding address may be placed on the enclosed letter so that it will appear through the window 19 which is on the front of the finished envelope.

The flap 14, if provided with pressure sensitive adhesive, should be left open until the envelope is finally sealed. For moisture activated adhesives the flap may be folded over since the facing portions will not adhere upon contact. As is shown in FIGS. 4 and 5, the flap 14 is of sufiicient dimensions as to .cover entirely the openings of the two compartments. It will also be noted that the shoulder portions 28 and 29 of the pleats effectively close off the upper corners of the envelope throughout the full range of expansion.

The V joint, formed by folding the front and rear panels along the fold line 17, will open into a box joint when the larger compartment is expanded. Crease lines 36 and 38 have been formed in each of the panels parallel to the fold line 17 with the crease line 36 extended across the pleats and along the intermediate panel sections 22 and 24. Diagonal crease lines 40 and 42 are formed at the lower portions of the pleats, the line 40 starting at the intersection of fold line 26 and crease line 36 and terminating at the bottom of fold line 30. The crease line 42 starts at the intersection of fold line 18 and crease line 36 and terminates also at the bottom of fold line 30. The crease line 38 will be seen as terminating at the point where the diagonal portion 33 merges with the front panel 16. With this arrangement, an expansible box joint is formed when the blank is folded in the manner already described. Conventional envelope folding machines may be used to form'the blank into an envelope since the front panel section is simply folded over.

In FIGS. 6 through 10 there is illustrated a modification of the FIGS. 1 through envelope. This embodiment is best suited for fabricating relatively large size envelopes, although the modification may also be applied to envelopes having relatively small dimensions.

As best seen in FIG. 6, an envelope blank 50 is generally T-shaped in plan view having a rectangular rear panel section 52 to which a front panel section 54 is hinged along fold line 56. A gummed flap 58 is hinged to the front panel section 54 along fold line 60 and intermediate panel sections 62 and 64 extend from opposite sides of the rear panel section 52 and are hinged thereto by means of accordion pleat sections 66 and 68. It will be noted that the upper ends of the accordion pleat sections extend as ears 70 and 72 out from the upper edges of the rear panel section. These ears, when folded, serve to seal off the upper corners of the envelope when'the gummed flap 58 is subsequently folded into a sealing position.

A rectangular window 74 is formed through the front panel section 54 and serves the same function as the window 19 in the FIG. 1 embodiment. As illustrated in FIG. 8 the envelope is put together by folding inwardly the accordion pleat sections and folding the intermediate panel sections 62, 64 back in overlapping relation against the rear panel section 52. The opposing marginal edges of the intermediate panel sections are coated with an adhesive as before so that they may be bonded together to form an expansible compartment. Next, the front panel section 54 is folded over the folded intermediate panel sections (see FIG. 10) to form a second compartment adjacent to the first. Facing marginal edges of the opposing panels are bonded together by adhesive to seal three sides of the compartment. The envelope itself is sealed by folding the flap 58 down against the rear panel section 52.

By forming the envelope so that the flap is hinged to the front panel section and folded onto the rear panel section, it is possible to make the flap as large as desired without it obscuring the address. It will be understood that if the flap were arranged to fold down over the front panel section, it would have to be of rather narrow dimensions so as not to cover the window 74.

While the invention has been described with particular reference to the illustrated embodiments, it will be understood that a number of modifications will appear to those skilled in the art without departing from the scope and spirit of the invention.

Having thus described the invention, what I claim and desire to obtain by Letters Patent of the United States is:

A duplex envelope, comprising a single blank of sheet material, said blank having a rectangular rear panel section, accordion pleat sections extending from opposite side edges of said rear panel section, ears formed in the upper margins of said pleat sections, intermediate panel sections extending from said pleat sections, said intermediate panel sections being of sufficient length that the ends thereof will overlap to form an expansible first compartment when folded back upon said rear panel section and joined, said intermediate panel sections being of a height somewhat less than that of said rear panel section whereby the lower edges of said intermediate panel section are even with the lower edges of said rear panel section while the upper edges of said intermediate panel sections extend below the upper edges of said rear panel section, a rectangular front panel section being hinged to the lower edge of said rear panel section and adapted to form a second compartment when folded back against the folded intermediate panel sections and joined along its two side margins, diagonal portions extending between said pleat sections and said front panel section, said front panel section being of substantially the same width as said rear panel section but of a height somewhat greater than said rear panel section and said intermediate panel sections whereby the upper end edge of the folded front panel section will extend over the upper edges of the folded intermediate panel sections, said front panel section being formed with an opening therein, means for bonding the side marginal edges of said front panel section to said intermediate panel sections, means for bonding together the free ends of the folded intermediate panel sections and a flap hinged along the upper edge of said rear panel section and adapted to fold over the folded first panel section to seal both of said compartments.

References Cited in the file of this patent UNITED STATES PATENTS 837,228 Jackson Nov. 27, 1906 851,117 Cataldi Apr. 23, 1907 2,055,716 Berkowitz Sept. 29, 1936 2,945,617 Normandin July 19, 1960 

